Fire extinguisher



Patented May l, 1934 FIRE EXTINGUISHEB.

John M. Melick, Cresskill, N. J., assignor to Ball TelephoneLaboratories,

Incorporated, New

York, N. Y., a corporation o1 New York Application June 30, 1932, SerialN0. 620,082

2 Glaims. (GI. 169-31) This invention relates to fire extinguishers andmore particularly to fire extinguishers of the type in which a fireextinguishing medium is expelled from a. tank by pressure re1eased froma.

cartridge within the tank.

'I'he obje ct of this invention is to prevent freezing 'at the outletend of the cartridge ca.se during the escapement of fluid from thecartridge case into the tank.

A feature of this invention resides in a. stem for puncturing thecacrtridge which serves as an aspirator a.nd permits sufficientcirculation of the fire extinguishing medium around the puncturingportion cf the stem and across the outlet end of ehe cartridge case toprevent freezing a.t the point at which the fluid under pressure is escaping into the tank.

In the drawing, Fig. 1 is a side elevational view partly in section ofa, fire extinguisher embodying this invention;

Fig. 2 shows a, fragment of the upper portion of a cartridge case insection am]. a. fragment 01' a stem puncturing the cartridge case;

Fig. 3 is a. view in section ta.ken 011 the line 33 in Fig. 2 and showsa fragment of the upper portion of the cartridge case and a fragment ofthe stem puncturing the cartridge case; and

Fig. 4 is an exploded view part1y in section of a cartridge case, a,coupling for holding the cartridge case suspended within the main tankof the extinguisher from a. screw cap of the tank a.nd gaskets forpreventing the entrance of meisture 130 end and neck portions 01 thecartridge case.

Fire extinguishers of the type shown in Fig. 1 are usually filled with achemical in liquid form which serves as a fire extinguishing medium. T0expell the fire extinguishin chemical from the tank with sufiicientforce so reach a. fire, gas he1d under pressure within a, cartridge casesupported within the tank, is released from the cartridge case anda11owed 130 escape into the sank.

There are some instances, however, when in putting out a, fire the useof fire extinguishing chemical is fo1md undesirable. 'I'his ispartieularly true in the extinguishment of fires 00cm- Iing amongdelicately adjusted mechanical am].

electrical elements or comparatively close networks cf wires such, forinstance, as found in 50 telephone equipment in central stations. Whenfire extinguishing chemical is used in xtinguishing a. fire occurringamong telephone relays switches or wire networks, considerable damage isdone 170 the apparatus by reason of the 001- 55 rosive efiects of thechemical on the comparative- 1y closely spaced contacts and the inherentadhesive properties of the chemical in sticking to the apparatus partsupon which it happens to fall. In addition to the damage caused by thefire a.nd the corrosive effects of the chemical fire extinguishingmedium, there is also a considerable 10ss due to the time required inremoving the chemical from the apparatus a.nd reconditioning theapparatus for service again. It has therefore been found advisable inextinguishing fires in some instances to use water as the fireextinguishing medium in plane of a chemical. When wa.ter is used as thefire extinguishing medium, the parts to which it is applied and whichare not damaged by fire may be quickly dried out and restored 120operable condition.

A cartridge of carbon dioxide under pressure has been found a.satisfactory mequm for crea.ting sufi'icient pressure within a tank ofwater to expe1l the wa'uer from the tank. Applicant has found, however,by actual experience that when s. comparatively sma1l puncture is madein a ca.rtridge case containing carbon dioxide a.nd the carbon dioxideis allowed to escape through the aperture into the water in the tank,freezing occurs at the point 01 puncture. 'I'he freezing at the point ofescapement of the carbon dioxide from the cartridge case into thewater-filled ta.nk results in either complete stoppage of the flow ofcarbon dioxide into the ta.nk er an intermittent flow and hence eithercomplete cessation 01 the flow of water from the tank 130 the fire or anintermittent fiow so inefiective asto render the fire extinguishercomparaoively useless for the purpose intended.

In the present invention a stem for puncturing the cartridge case isprovided which permits suflicient circulation of water or other fireextinguishing medium around the point of puncture in the cartridge case130 prevent freezing at this point.

For a complete description of this invention, reference will now be hadto the various figures in the drawing in which like parts bear 1ikenumerals and in which 1 is a comparatively large tin-lined copper tankhaving an annular base 2, a top portion 3, a. handle 4, a screw cap 5and an out1et connection 6, across the inner end of which is aperforated platze 7. 'I'he screw cap 5 is screw-threadedly attached to acomparatively 1arge annular filler connection 8 located in the topporuion 3 of the tank 1 and is provided with a comparatively 1argediameter ring-shaped hau: grip 9 which is connected to the screw cap 5by spokes 10. The top of the screw cap 5 has an upwardly extendingannular centrally 1ocated boss 11 and a tln 12 extending' radially fromthe boss 11. The boss 11 is internally threaded to receive the smallerexternally threaded end-o1 a reducing coupling 13 which is screwed intothe threaded boss 11 1mm the underside of the screw cap 5, the largerextemally threaded end 14 of the reducing coupling 13 extending downwardfrom the underside of the screw cap through the filler connection 8 and.towards the interior of the tank 1.

Supported within the tank 1 is a cartridge case 15 containing a chargeof carbon dioxide under pressure. 'Ihis cartridge case 15 is abottleshaped casing cf steel having an enlarged lower end portion, anexternally threaded neck portion 16 and an upper reduced e nd portion17. The Walls of the cartridge case 15, as shown in section in Fig. 4,are comparatively thick. The wall, however, at the extreme upper end ofthe reduced end portion 17 is considerably reduced in thickness as shownat 18 in Figs. 2, 3 and 4 to provide a comparatively thin wall sectionwhich may be punctured when it is desired to allow escapement of thecarbon dioxide from the cartridge case 15 to ehe tank 1. T0 preventcorrosion 015 the steel cartridge case and electrolytic action betweenthe st eel of the cartridge case and the inner wall sur1'ace of the tank1 which would result in pitting of the steel Wall of the cartridge caseand finally a.llow escapement of the carbon dioxide from the cartridgecase into the tank 1, the enlarged portion 01 the cartridge case 15 isenclosed in a. lead shirt as shown in section at 19 in Fig. 4. 'Ihislead shirt encloses the whole of the lower section of the cartridge case15 and extends up to the threaded neck portion 16. The threaded neckportion 16 and reduced end 17 and the outer surface of the reduced wallat 18 are tinnecl to prevent corrosion of these parts.

The cartridge case 15 is suspended within the tank 1 from the reducingcoupling 13 by means of a. sleeve 20 which is internally threaded at 21to engage the externally threaded larger end 14 of the reducing coupling13 and internally threaded at 22 to receive the externally threaded neckportion 16 of the cartridge case 15. An annular inwardly extendingbeveled shoulder 23 is provided about midway of the ends of sleeve 20 toform a. receptacle for the reduced end portion 17 of the cartridge case15. Between the shoulder 23 and. the interiorly threaded end 21 are twocomparatively lauge side outlet ports 2424. A cap gasket 25 of lead,apertured at the top, is fitted over the reduced end 17 of the cartridgecase 15 and compressed against the internally extending annular beveledshoulder 23 of the sleeve 20 to prevent moisture from gaining 9.ccess tothe reduced end portion 17 of the cartridge case 15. The lower portionof the sleeve 20 is flared out in the form of a hell at 26 and providedwith an outwardly extending annular offset 27 to accommodate the lowerend of the neck portion o1 the cartridge case 15. 'Io prevent moistureIrom gaining access 130 the threaded neck portion 16 0f the cartridgecase 15 in the region of the lower portion 01 the sleeve 20 a rubberring gasket 28 is slipped over the neck of the cartridge case 15 andcompressed against the inner wall surface of the annular offset 27 ofthe sleeve 20.

'Io puncture the cartriclge case 15 ab the reduced wall portion 18 a.stem 29 is provided. The stem 29 which is adapted 120 movelongitudina.lly within the reducing coupling 13, comprises a. shankportion 30 which extends upward through the reducing coupling 13 to theoutside o1! the extinguisher and an enlarged lower cylindrical end 31which extends downward within the tank. The lower portion o! theenlarged' lower cylindrical end 31 01 the stem 29 is chamfered onopposite sides and cut down to form a spade end 32 having three spacedpr0ngs in parallel, the central prong being about. twice the length ofthe other two and Iorming a cylindrica.l puncturing pin 33 forpuncturing the cartrldge case 15 at the point 18 where the wall of thecartridge case 15 has been reduced in thickness. A groove 34 is-providedin one side of the puncturing pin 33 to allow escapement of the carbondioxide from the cartridge case 15 when the puncturing pin 33 is thrustthrough the reduced wall portion 18. The groove 34 does not extend thefull length of the puncturing pin 33 but starts at a point slightlyabove the lower extremity of the pin and extends upward into the curvedportion of the chamfer as shown in Figs. 1, 2 and 3. When the puncturingpin 33 is driven through the reduced wa.ll portion 18 o1 the cartridgecase 15 as shown in Figs. 2 and 3 it makes a round hole in the reducedwall portion 18 and is thrust far enough through so tha.t the full roundsolid end of the puncturing pin extends below the inner surface of thereduced Wall portion 18 and the lower end of the groove 34 is within thecartridge case 15. Carbon dioxide within the cartridge case 15 thenescapes from the cartridge case 15 into the tank 1 by way of the groove34 and the side outlet ports 24-24 01" the sleeve 20. The two outsideprongs 3535 on the spade portion 32 of the stem 29 rast on the top ofehe carbridge case 15 and limit the extent of thrust of the puncturingpin 33 through the reduced Wall portion 18 cf the cartridge case 15 andin cooperation with the puncturing pin 33 form two arch-like channels onopposite sides of ehe puncturing pin 33 for circulation of the wa.ter orother fire extinguishing medium across the top of the cartridge ca.se15. Between the enlarged lower cylindrical end 31 and the shank portion30 of the stem 29 is an outwardly projecting annular shoulder 36 whichbears against the inner Wall surfa.ce of the larger end 14 of ehereducing coupling 13 and the inner Wall surface of an inwardlyprojecting annular shoulder 37 provided in the upper portion of thesleeve 20 as shown in Fig. 1.

011 the outer end of the stem 29 is an impact knob 38 to receive a. blowadministered to the stem 29 when the puncturing pin 33 is to be thrustthrough the reduced wall portion 18 01 the cartridge case 15. The impactknob 38 has an inverted cone-shaped upper portion terminatmg in acylindrical lower portion which is longitudinally bored to accommodatethe outer end.of the shank 30 of the stem 29. Laterally projecting fromthe lower cylindrical portion of the impact knob 38 is a lug 39 anddir'ectly below the lug 39 and extending in the same direction is a pairof spaced fingers 40, only one of which is shown in Fig. 1. The lug 39is beveled on its undersurface and cooperates with a spring pressed holt41 supported by a bracket 42 on the fin 12 to hold the stem 29 in itsprojected position and driven through the reduced wall portion 18 of thecartridge case 15. The spaced fingers project on opposite sides of thebracket 42 and prevent rotation of the stem 29.

In operating the fire extinguisher a. blow is delivered to the impactknob 38 sufiicient to drive the stem 29 inward. of the tank 1. This maybe conveniently done by turning the extinguisher upside down and drivingthe impact knob 38 against a floor surface. The stem 29 thereby isdriven inward of the tank 1 and the puncturing pin 33 of the stem 29 isthrust through the reduced wal1 portion 18 0f the cartridge case 15. Thelug 39 on the impact knob 38 is driven agdinst the spring pressed holt41 and causes suflicient displacement of the holt 41 to allow the 1ug 39to pass. When the lug 39 passes the holt 41 the spring pressed holt 41again resumes its normal position and prevents withdrawal of thepuncturing pin 33 from the cartridge case 15. Carbon dioxide then beginsto escape from the cartridge case 15 by way of the groove 34 in thepuncturing pin 33 and passes through one of the ports 24 of the sleeve20 into the tank 1 and exerts sufiicient pressure in the tank 1 to expe1the water from the tank, the water finding an outlet through theapertured plate 7 and outlet connection 6 from whence it flows throughthe hose 43 and nozzle 44 with sucient force 130 be directed to thefire.

When the carbon dioxide begins 130 escape from the cartridge case 15 byway 01 the groove 34 in the puncturing pin 33 it sets up an aspiratorefiect around the point of puncture in the reduced wall portion 18 andStarts a cixculation cf water across the point of puncture, the waterbeing drawn through the port 24 opposite to that which faces the groove34 and passing across the punctured end of the cartridge case 15 andaround the puncturing pin 33 by way cf the arch-like channels formed. bythe outer prongs 3535 and the puncturing pin 33. Circula.tion of wateraround the puncturing pin 33 continues as long as the carbon dioxidecontinues to escape and prevents freezing at the point cf puncture.

What is claimed is:

1. In a fire extinguisher comprising a tank comtaining water and a.cartridge of compressed fluid supported within the tank, a stem ha.vinga pin portion to be thrust into said cartridge to a11ow escapement ofsaid compressed fiuid into the tank, and a pair of fins projecting fromsaid stem, said fins projecting parallel to said pin portion and spacedtherefrom to form channels for circulation of the water in the tankaround said pin when sa.id pin is thrust into said cartridge and thecompressed fluid is escaping into the Trank.

2. In a fire extinguisher comprising a tank comtaining water, and acartridge containing fiuid under pressure supported Within the tank, arnovable stem having a free end pin portion to be thrust into saidcartridge, said pin portion having a. recess formed in one sideproviding a channel for escapement of the fiuid from said cartridge, andfins projecting from said stem parallel to said pin and spaced from saidpin to limit the extent of thrust of said pin into said cartridge andforming in cooperation with sa.id pin and an end 01 said cartridge,channels for circulation of the water in said tank around the pinportion and across an end of said cartridge.

JOHN M. MELICK.

